1. Field of the Invention
The invention relates to a manufacturing method for a segment coil.
2. Description of Related Art
In recent years, a motor has been widely used, which uses segment coils as coils that structure a stator of the motor. In the motor using the segment coils, it is possible to improve a space factor of a slot effectively, thereby realizing size reduction, high performance, and high output of the motor.
Japanese Patent Application Publication No. 2009-199749 (JP 2009-199749 A) discloses a technique regarding a manufacturing method for an assembled conductor. In the technique disclosed in JP 2009-199749 A, a plurality of element wires are stranded together to form a stranded wire, and thereafter, the stranded wire is compression-molded by using a forming die, thereby forming a rectangular conductor in which the stranded wire has a rectangular section. Then, an outer periphery of the rectangular conductor is covered by using an insulating material such as a resin material so that an insulation layer is formed. Thus, an assembled conductor is formed.
In a case where segment coils are used as coils that structure a stator of a motor, a plurality of U-shaped segment coils are arrayed into a circular shape in a stator core, and the plurality of segment coils are electrically connected with each other. At this time, since a plurality of coil end portions of the segment coils are connected with each other by welding and so on, it is necessary to bend the segment coils so that the plurality of coil end portions come close to each other.
However, because the segment coils are coils that are formed by assembling a plurality of element wires (conductors), the element wires in the coil end portions come apart when the segment coils are bent, and it could thus be difficult to connect the plurality of coil end portions with each other by welding and so on.